/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.skatiger.jrove.util;

import java.io.IOException;
import java.io.Writer;

public final class FastWriter extends Writer {

    private char[] buff;
    private int size;

    public FastWriter() {
        this(1024);
    }

    public FastWriter(int initialSize) {
        if (initialSize < 0) {
            throw new IllegalArgumentException("Initial Size cannot be less than 0");
        }
        this.buff = new char[initialSize];
    }

    @Override
    public void close() throws IOException {
        // do nothing
    }

    @Override
    public void flush() throws IOException {
        // do nothing
    }

    private final void overflow(int len) {
        if (this.size + len > this.buff.length) {
            char[] next = new char[(this.size + len) * 2];
            System.arraycopy(this.buff, 0, next, 0, this.size);
            this.buff = next;
        }
    }

    public void reset() {
        this.size = 0;
    }

    @Override
    public String toString() {
        return new String(this.buff, 0, this.size);
    }

    @Override
    public void write(char[] cbuf) throws IOException {
        this.write(cbuf, 0, cbuf.length);
    }

    @Override
    public void write(char[] cbuf, int off, int len) throws IOException {
        overflow(len);
        System.arraycopy(cbuf, off, this.buff, this.size, len);
        this.size += len;
    }

    @Override
    public void write(int c) throws IOException {
        this.overflow(1);
        this.buff[this.size] = (char) c;
        this.size++;
    }

    @Override
    public void write(String str) throws IOException {
        this.write(str.toCharArray(), 0, str.length());
    }

    @Override
    public void write(String str, int off, int len) throws IOException {
        this.write(str.toCharArray(), off, len);
    }
}